We report strong diffraction of cold neutrons from an only 30 micro m thick holographic polymer-dispersed liquid crystal (H-PDLC) transmission grating. The light-induced refractive-index modulation for neutrons is about 10(-6), i.e., nearly 2 orders of magnitude larger than in the best photo-neutron-refractive materials probed up to now. This makes H-PDLCs a promising candidate for fabricating ...

It is shown that the observation of the spectra of leading neutrons from proton beams can be a good probe of absorptive and migration effects. We quantify how these effects modify the Reggeized pion-exchange description of the measurements of leading neutrons at HERA. We are able to obtain a satisfactory description of all the features of these data. We also briefly discuss the corresponding da...

Based on a study of high-energy epithermal (HEE) neutrons in data from the Lunar Exploration Neutron Detector (LEND) on NASA's Lunar Reconnaissance Orbiter (LRO), the background from HEE neutrons is larger than initially estimated. Claims by Mitrofanov et al. (Reports, 22 October 2010, p. 483) of enhanced hydrogen abundance in sunlit portions of the lunar south pole and quantitative hydrogen co...

Likemostmatter (with the exception of, say, neutron stars), proteins and peptides are mostly made of nothing – an ephemeral cloud of electrons with very little mass surrounding tiny and very dense atomic nuclei that contain nearly all of themass (i.e., peptides and proteins aremade of atoms). Atoms havemass and the unit ofmass that is most convenient to use is called the atomic mass unit (abbre...

The neutron direct radiative capture (DRC) process is investigated, highlighting the role of incident p-wave neutrons. A set of calculations is shown for the 12 C(n, γ) process at incoming neutron energies up to 500 keV, a crucial region for astrophysics. The cross section for neutron capture leading to loosely bound s, p and d orbits of 13 C is well reproduced by the DRC model demonstrating th...

A neutron camera with liquid scintillator detectors is used in MAST to measure the neutron emissivity from D(d,n)(3)He reactions along collimated lines of sight. In this work, the measured recoil proton pulse height spectra generated in the detectors by the incident neutrons is modelled taking into account the energy spectrum of the generated neutrons, their spatial distribution and transport t...

The present work contains some results of observations of neutron flux variations near the Earth’s surface. The Earth’s crust is determined to be a significant source of thermal and slow neutrons, originated from the interaction between the nuclei of the elements of the Earth’s crust and the atmosphere and α−particles, produced by decay of radioactive gases (Radon, Thoron and Actinon). In turn,...

The structure of the crust of a neutron star is completely determined by the experimentally measured nuclear masses up to a density of the order of 1011 g.cm−3. At higher densities, the composition of the crust still remains uncertain, mainly due to the presence of “free” superfluid neutrons which affect the properties of the nuclear “clusters”. After briefly reviewing calculations of the equil...

The adsorption of barium ions on barium titanate in an aqueous solution was studied by means of batch technique as a function of Ba(II) concentration, temperature and solution pH using Ba-140 as radiotracer. The results show that adsorption is essentially complete in ca 180min and the steady state values of adsorption at various concentrations agree well with the classical Freundlich isotherm a...